While running vircryptotest, it was found that valgrind pointed out the
following error:
==27453== Invalid write of size 1
==27453== at 0x4C7D7C9: virCryptoHashString (vircrypto.c:76)
==27453== by 0x401C4E: testCryptoHash (vircryptotest.c:41)
==27453== by 0x402A11: virtTestRun (testutils.c:199)
==27453== by 0x401AD5: mymain (vircryptotest.c:76)
==27453== by 0x40318D: virtTestMain (testutils.c:782)
==27453== by 0x3E6CE1ED1C: (below main) (libc-start.c:226)
==27453== Address 0x51f0541 is 0 bytes after a block of size 65 alloc'd
==27453== at 0x4A0577B: calloc (vg_replace_malloc.c:593)
==27453== by 0x4C69F2E: virAllocN (viralloc.c:189)
==27453== by 0x4C7D76B: virCryptoHashString (vircrypto.c:69)
==27453== by 0x401C4E: testCryptoHash (vircryptotest.c:41)
==27453== by 0x402A11: virtTestRun (testutils.c:199)
==27453== by 0x401AD5: mymain (vircryptotest.c:76)
==27453== by 0x40318D: virtTestMain (testutils.c:782)
==27453== by 0x3E6CE1ED1C: (below main) (libc-start.c:226)
==27453==
...and many more. Two observations: hashstrlen was already set
to include the trailing NUL byte (so writing to hashstrlen as
the array offset was indeed writing one byte beyond bounds), and
VIR_ALLOC_N already guarantees zero-initialization (so we already
have a trailing NUL without needing to explicitly write one).
Signed-off-by: Eric Blake <eblake@redhat.com>
GNULIB provides APIs for calculating md5 and sha256 hashes,
but these APIs only return you raw byte arrays. Most users
in libvirt want the hash in printable string format. Add
some helper APIs in util/vircrypto.{c,h} for doing this.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
